Hypertension occurs commonly and early in the natural history of autosomal dominant polycystic kidney disease (ADPKD). Hypertension (HBP) has been shown to have an adverse effect on both patients and renal outcome in ADPKD. Moreover, left ventricular hypertrophy (LVH), a known risk factor for cardiovascular mortality and sudden death, occurs frequently in HBP ADPKD patients. At present it is not clear what is the optimal level of blood pressure reduction in HBP ADPKD patients to minimize loss of renal function or to reverse lVH. Given that hypertension is the most important treatable variable to affect renal and patients outcome in ADPKD, this project will determine in prospective longitudinal fashion the appropriate level of blood pressure control in HBP ADPKD patients. Secondly, since lVH also occurs in normotensive ADPKD patients, factors other than HBP or the ADPKD gene may play a role in the development of lVH in ADPKD patients. Given that activation of the renin-angiotensin-aldosterone axis is important in ADPKD and that the deletion polymorphism of the angiotensin converting enzyme gene is associated with LVH, normotensive and HBP ADPKD patients with and without LVH will be studied with regard to the frequency of this genotype. As well, given that hypertension in the unaffected parent is associated with earlier and more frequent HBP in ADPKD patients, the frequency of the angiotensinogen gene variant M235T will also be studied with regard to onset of hypertension and frequency of preeclampsia in ADPKD patients.